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The Lowdown on Low Blood Pressure

Most people worry about having high blood pressure. For a few people, however, low blood pressure, or hypotension, is a major concern.

Current guidelines identify optimal blood pressure as less than 120/80. The National Heart, Lung, and Blood Institute defines hypotension as a blood pressure lower than 90/60. There is no specific lower limit that is defined as unhealthy. Elderly people, however, may have symptoms of dizziness and lightheadedness when their blood pressure drops lower than usual. But most people with blood pressure in the lower ranges are young and healthy, and have no symptoms.

What are the symptoms?

According to the American Heart Association (AHA), these are symptoms of low blood pressure:

Dizziness or lightheadedness

Fainting

Lack of concentration

Blurred vision

Nausea

Cold, clammy, pale skin

Rapid, shallow breathing

Fatigue

Depression

Unusual thirst

These are possible causes of low blood pressure:

Medications, including antianxiety drugs, heart medications, drugs for Parkinson's disease, tricyclic antidepressants, erectile dysfunction drugs, particularly in combination with nitroglycerine, narcotics, or alcohol. Other prescription and over-the-counter medications may cause low blood pressure when taken in combination with drugs for high blood pressure.

Postural hypotension, or a sudden decrease in pressure that occurs when you stand up after sitting or lying down. This can cause dizziness, blurred vision, and fainting.

Genetics. Some people have naturally low blood pressure because of their genes.

Pregnancy

Severe infection

Treatment

Many healthy people who do have chronically low blood pressure and no symptoms require no treatment. Most people with chronic low blood pressure who have symptoms can be safely treated with medication and lifestyle changes.

The following actions may help control the problem:

Drink more water, and avoid alcohol because it can be dehydrating.

Slow down. You may be able to reduce lightheadedness by taking it easy when you move from a prone to a standing position. Instead of jumping out of bed in the morning, for instance, sit up on the edge before standing and wiggle your feet and move your legs. This will get your heart rate up and increase circulation.